This paper focuses on the problem of handling impacts by means of an aerial manipulator and proposes a solution that combines the control of the aerial manipulator's end-effector position with an innovative manipulation system consisting of both active and passive joints. The approach aims at limiting the influence of impacts on the controlled attitude dynamics in order to allow the aerial manipulator to remain stable during and after impact. The developed concept is intended to convert kinetic energy into potential energy, which is permanently stored into elastic bands by means of a directional locking mechanism. The proposed approach has been validated through experiments, in comparison with a rigid manipulator. The results show that, compared with the case of a rigid manipulator, the proposed approach and the developed mechanical system achieve stable impact absorption without bouncing away from the interacting environment.

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On‐site inspection of large‐scale infrastructure often involves high risks for the operators and high insurance costs. Despite several safety measures already in place to avoid accidents, an increasing concern has brought the need to remotely monitor hard‐to‐reach locations, for which the use of aerial robots able to interact with the environment has arisen. In this paper a novel approach to aerial manipulation is presented, where a compact manipulator with a single degree‐of‐freedom is tailored for the placement and retrieval of sensors in the environment. The proposed design integrates on‐board sensing, a high‐performance force controller on the manipulator, and a thrust‐to‐force mapping on the flight controller. Experimental results demonstrate the high reliability achieved during both placement and retrieval tasks on flat surfaces (e.g., a bridge wall) and cylindrical surfaces (e.g., tree trunks). A total number of 89 flight experiments were carried out to demonstrate the robustness and potential of the compact, bespoke aerial design.

This paper presents simulation and airborne test results for a quadrotor equipped with an actively-variable compliance manipulator for contact interaction. Typical applications of this type of manipulator might include sensor placement operations and non-destructive testing. It is shown that through the use of the proposed manipulator, the force experienced at the end-effector can be adaptively controlled, and the effect of interactions on the aircraft itself minimised. Simulation and airborne results show a consistent correlation between the peak loads experienced at the end-effector and the actuator gains. A lightweight, adaptively-compliant actuator of this type offers the opportunity not only to tailor different demanded forces at the end-effector, but also to shape the loads applied-effects which can be achieved by changing only the software structure and tuning of the actuator control system.